Replacing it won’t be cheap or easy. Salt is both inexpensive and indispensable to food manufacturers for a number of reasons. Aside from making food taste better — think Fourth of July barbecue — it also retards bacteria growth and acts as a preservative.

“Certain categories will obviously face challenges when it comes to sodium reduction, given the functional role salt plays in flavor, texture and food safety,” Stephanie Pauk, global food science analyst at Mintel, said via email.

Americans consume more than 3,400 milligrams of sodium a day, compared to the 2,300 milligrams recommended by the FDA. (Some demographics, like older people and those with high blood pressure, are advised to keep it to 1,500 milligrams.) FDA Commissioner Margaret Hamburg told The Associated Press recently that the agency hoped to discuss its plans on food company guidelines “relatively soon.”

Hamburg told the AP that the FDA is concerned about Americans’ salt intake. The food industry, meanwhile, is concerned about finding acceptable stand-ins for a food-processing workhorse.

“Salt alternatives are typically more expensive and don't provide all the same benefits that salt does,” Pauk said.

Those benefits go beyond taste. “Salt is one aspect of the formulation and processing of foods that determines how bacteria will survive in foods,” said William Kerr, professor in the Food Science and Technology department at the University of Georgia, via email. So taking out salt could have implications for food safety and shelf stability.

“We’ve been working on this for years and it’s been small steps,” said Michael Antinone, research and development director for Progresso, a General Mills brand. General Mills said in 2010 it planned to lower sodium by 20 percent across “multiple product categories” by 2015. Antinone said herbs and spices, as well as cooking techniques such as roasting or stewing, help add and concentrate flavor without salt.

It will be easier for behemoths like PepsiCo and Kraft Foods, which have bigger R&D budgets to throw at the problem. “There will be … costs of reformulating and optimizing the flavor of products,” Kerr said. Although the FDA has indicated it intends to make its guidelines voluntary, smaller manufacturers could struggle to come up with lower-sodium versions of their products.

An indirect expense is the R&D and manpower sodium reduction requires.

“It’s a lot of work just to take it out,” said Mark Andon, vice president of nutrition and food labeling for ConAgra Foods. “We could be innovating in other ways — introducing new products, enhancing the flavors of existing products, offering line extensions. It’s a zero-sum game. If you’re focusing on sodium, you’re not doing something else.”

“I don’t think it’s a stretch to say for anybody that’s doing this, especially a company as large as ConAgra, it’s tens of millions of dollars,” Andon said. Five years ago, ConAgra started an initiative to reduce sodium across its portfolio by 20 percent, which it finished last year.

“Just taking it out will, in most cases, alter the consumer experience with that product. That is something that should not be approached lightly,”

Even big companies are leery of sinking resources into fiddling with flavors and textures consumers know and like because it can backfire. Three years ago, the Campbell Soup Co. added some salt back into certain varieties of soups in which it had lowered the sodium content.

Antinone said reformulating some soups to contain less sodium could take as little as six to nine months. “Others, we’re still working on because they’re really hard,” he said. “As a developer, the hardest thing to do is to match something that already exists.”

The implications of any FDA recommendations could affect the restaurant industry, too. Since about three-quarters of the salt we eat comes from eating processed foods and restaurant meals, big fast-food chains will face a challenge.

Darren Tristano, executive vice president at Technomic Inc., said restaurants that already use fresh ingredients won’t have as tough a transition. They’ll have to invest in research, but they’ll have more options when it comes to creating new recipes that highlight spices or other flavors besides salt.

“The cost for fast food (McDonalds, Taco Bell, etc.) … will be much more costly,” Tristano said via email. He predicted that the pass-through cost to consumers would be “modest,” but he warned that drive-through devotees might need to prepare their taste buds for a change. “Consumers will need to adapt to the change in flavor for items that have been consistently prepared for decades,” he said.

Ultimately, “It will take time and money to make the changes, and it will take time for consumers to accept different tasting products,” Kerr said.

“Just taking it out will, in most cases, alter the consumer experience with that product. That is something that should not be approached lightly,” Andon said. “It doesn’t take a lot to turn people away .... If they have a bad experience once, they may not come back.”

By changing things slowly, companies hope to be able to gradually tweak America’s palate without prompting diners to reach for the salt shaker.

“[Companies] that can afford it already are investing in ways to reduce sodium in their products,” Kerr said. He suggested companies saw the writing on the wall or thought they could gain a competitive edge by promoting their products as healthier.

They probably won’t be shouting those health claims from the rooftops, though — at least not initially. According to research published in the journal Public Health Nutrition, low-sodium labels can turn off consumers — and makes them more likely to add salt themselves. As a result, some companies are lowering sodium without advertising it on packaging.

“We've seen the sodium levels going down in some categories, suggesting that companies are engaging in a stealth approach to sodium reduction,” Pauk said. “By reducing sodium slowly over time, changes are less noticeable and are more palatable.”